1 /* 2 * Copyright 2007 Kasper B. Graversen 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package org.supercsv.cellprocessor; 17 18 import org.supercsv.cellprocessor.ift.BoolCellProcessor; 19 import org.supercsv.cellprocessor.ift.CellProcessor; 20 import org.supercsv.cellprocessor.ift.DateCellProcessor; 21 import org.supercsv.cellprocessor.ift.DoubleCellProcessor; 22 import org.supercsv.cellprocessor.ift.LongCellProcessor; 23 import org.supercsv.cellprocessor.ift.StringCellProcessor; 24 import org.supercsv.util.CsvContext; 25 26 /** 27 * This processor returns a specified default value if the input is <tt>null</tt>. This is handy when writing partially 28 * filled beans, maps and arrays, as for each column a default value can be specified. 29 * <p> 30 * To return the String <tt>""</tt> when a null is encountered use <code> 31 * new ConvertNullTo("\"\""); 32 * </code> 33 * <p> 34 * If you need further processing of the value in case the value is not <tt>null</tt>, you can link the processor with 35 * other processors such as <code> 36 * new ConvertNullTo("\"\"", new Truncate(3)) 37 * </code> 38 * 39 * @since 1.20 40 * @author Kasper B. Graversen 41 */ 42 public class ConvertNullTo extends CellProcessorAdaptor implements BoolCellProcessor, DateCellProcessor, 43 DoubleCellProcessor, LongCellProcessor, StringCellProcessor { 44 45 private final Object returnValue; 46 47 /** 48 * Constructs a new <tt>ConvertNullTo</tt> processor, which returns a specified default value if the input is 49 * <tt>null</tt>. 50 * 51 * @param returnValue 52 * the value to return if the input is <tt>null</tt> 53 */ 54 public ConvertNullTo(final Object returnValue) { 55 super(); 56 this.returnValue = returnValue; 57 } 58 59 /** 60 * Constructs a new <tt>ConvertNullTo</tt> processor, which returns a specified default value if the input is 61 * <tt>null</tt>. If the input is not <tt>null</tt>, then the next processor is executed. 62 * 63 * @param returnValue 64 * the value to return if the input is <tt>null</tt> 65 * @param next 66 * the next <tt>CellProcessor</tt> in the chain 67 * @throws NullPointerException 68 * if next is null 69 */ 70 public ConvertNullTo(final Object returnValue, final CellProcessor next) { 71 super(next); 72 this.returnValue = returnValue; 73 } 74 75 /** 76 * {@inheritDoc} 77 */ 78 public Object execute(final Object value, final CsvContext context) { 79 if( value == null ) { 80 return returnValue; 81 } 82 83 return next.execute(value, context); 84 } 85 }